The invention relates to the modification of fats or fat blends so as to improve the crystallization characteristics thereof.
Fats per se or in the form of fat blends often suffer from problems during crystallisation. E.g. the crystallisation rate often is low or the crystal form of the fats results into products that are not sufficiently hard or are difficult to filter.
In order to cope with this problem the prior art discloses to add crystal modifiers to the fats, such as polymers or hardened fat components. The polymers however are not food grade and thus have to be removed from the food product which is not always easy and, if possible at all, complicates the processing, adding to the costs and making the use thereof economically unattractive. Hardened fats are not always healthy because of their high content of saturated fatty acid and have a negative impact on the viscosity and mouthfeel of the products.
Moreover crystal modifiers that are effective and that simultaneously add health benefits to the food products have not been disclosed yet in the prior art.
Therefore we studied whether we could find crystal modifiers that are effective for improving the crystallisation and the hardness of the product resulting therefrom and that simultaneously will add health benefits to the final food product. This study resulted in the finding that by adding a blend of ursolic acid and oleanolic acid to a fat per se or to a fat in a food product the crystallisation rate of the fat could be increased while simultaneously the hardness of the fat composition could be increased. Further it was found that the addition of the ursolic acid/oleanolic acid mixture also improved other properties of the total composition, such as oral mouthfeel; heat resistance; aeration properties and drying times (when applied in ice-cream coatings).
The known health effects of ursolic acid and oleanolic acid remain in the fat composition and/or the food product made thereof.
Health effects of ursolic acid and oleanolic acid can be found in eg JP 09/040689; JP 09.067249; CN 1085748; JP 1039973; JP 03287531; JP 03287530; EP 774255; JP 07258098; JP 07048260; JP 01132531; FR 2535203 and 10 JP 1207262.
Therefore our invention concerns in the first instance a blend of a vegetable fat and/or a blend of vegetable fats and at least 0.1 wt %, preferably 0.1 to 10 wt %, most preferably 0.2 to 5 wt % of a natural health composition, wherein the natural health composition comprises a mixture of ursolic acid and oleanolic acid in a weight ratio of 1:99 to 99:1, preferably 10:90 to 90:10, more preferably 75:25 to 25:75.
It was found that very beneficial fat compositions could be obtained if the fat in above blend displays a solid fat content measured on a non-stabilised fat by NMR-pulse at the temperature indicated of: 5 to 90 at 5xc2x0 C.; 2 to 80 at 20xc2x0 C. and less than 15 at 35xc2x0 C.
Non-stabilised being defined as a fat that has been subjected to the following temperature profile before measuring the fat content by NMR pulse: melt at 80xc2x0 C. and cool to 0xc2x0 C. and keep at 0xc2x0 C. for 30 min, than warm up to measurement temperature and keep at that T for 30 min before measuring the N value. Very useful blends were obtained by making a blend comprising components A, B and C, wherein
A=a natural health composition, comprising a mixture of ursolic acid and oleanolic acid in a weight ratio of 1:99 to 99:1
B=a solid fat with a solid fat content at 20xc2x0 C. of at least 20, measured on the unstabilised fat by NMR-pulse, preferably at least 45, most preferably at least 60 and
C=a fat with a content of fatty acids with 18 C-atoms with one to three double bonds of at least 40%, which components A, B and C are present in amounts of:
at least 0.1 wt % A, preferably 0.1 to 20 wt %, most preferably 0.2 to 10 wt %
8 to 90 wt % of B, preferably 25 to 75 wt %, most preferably 40 to 70 wt % and
0 to 85 wt % of C, preferably 15 to 65 wt %, most preferably 20 to 50 wt %.
Although fats B and C could be selected from a wide range of fats we prefer to use fats B that are selected from the group consisting of palm oil, palm oil fractions, cocoa butter, cocoa butter equivalents, palm kernel oil, fractions of palm kernel oil, hardened vegetable oils such as hardened palm oil, hardened fractions of palm oil, hardened soybean oil, hardened sunflower oil, hardened rape seed oil, hardened fractions of soy, rape or sunflower oil, mixtures of one or more of these oils and interesterified mixtures thereof.
Fats C that are most preferred are fats selected from the group consisting of sunflower oil, high oleic sunflower oil, olive oil, soybean oil, rape seed oil, palm oil olein, olein fractions from other vegetable oils, high oleic vegetable oils and cotton seed oil.
The natural health composition can contain ursolic acid and oleanolic acid as the only components (eg by mixing of these components isolated from natural sources) however we found that we could obtain better health effects without effecting the physical effects of the blend of ursolic acid and oleanolic acid in a negative sense if the health component also comprises isoflavonoids and/or flavonoids in particular in amounts corresponding with 0.005 to 5% of the total amount of ursolic acid and oleanolic acid.
Compositions containing the health components can be obtained from natural sources such as fruit skins, in particular skins of apples, pears, cranberries, cherries or prunes. All-spice oil is another natural source for ursolic acid/oleanolic acid mixtures. The health component can be obtained by extraction with a suitable organic solvent such as acetone.
Part of our invention are also food products having a fat phase in it and wherein the fat phase comprises at least partly the blends according to the invention. Examples of preferred food products are spreads (low fat or full fat), dressings, mayonnaises, cheese, creams, ice creams, ice cream coatings, confectionery coatings, fillings, sauces and culinary products.
Above food products preferably comprise 10 to 90 wt %, preferably 20 to 60 wt % of a continuous fat phase. The physical effects we describe above are the most pronounced in these products.
The modification in crystallisation behavior also results in a number of other effects that are also beneficial. Therefore our invention, according to another embodiment also comprises the use of a blend of ursolic acid and oleanolic acid in a fat blend per se or in a fat blend of a food product wherein the blend of ursolic acid and oleanolic acid is used to modify the crystallisation behavior of a fat blend or a fat blend in a final food product to
(i) increase the hardness of the fat blend or final product and/or
(ii) to improve the plasticity of the fat blend or final product and/or
(iii) to improve oral mouthfeel of the fat blend or final product and/or
(iv) to improve the heat resistance of the fat blend or final product and/or
(v) to increase the speed of crystallisation of the fat blend or final product and/or
(vi) to increase the aeration properties of the fat blend or final product and/or
(vii) to decrease drying times of ice-cream coatings.
According to a last embodiment our invention also concerns a process to make a blend with the composition according to the invention, wherein
(i) skins of a fruit such as apples, cherries, prunes, cranberries and pears are extracted with an organic solvent such as acetone
(ii) an extract of a mixture of ursolic acid and oleanolic acid is isolated and after removal of the solvent a mixture containing ursolic acid and oleanolic acid is obtained this mixture of acids obtained in (ii) is blended with a fat in the ratios required to obtain the compositions according to the invention.